JPH03177784A - Repairing of spout for electric furnace - Google Patents

Abstract

PURPOSE:To repair a spout without stopping an electric furnace for a long period of time or renewing the damaged spout by a method wherein a connecting part between the spout, whose length is shortened, and a material throwing tube is separated and a short tube, having the same length as the reduced length of the spout, is interposed in the connecting part after dismantling the short tube into a plurality of parts, then, the dismantled short tube is con nected to integrate them. CONSTITUTION:When a center spout 1, difficult to extract it to the outside of a furnace, is to be repaired, an electric furnace is stopped temporarily and the flange of connecting part between the centers pout 1 and a material throwing tube 2, which is provided on a furnace lid, is separated. Subsequently, the spout 1 is descended to provided an interval between the spout 1 and the material throwing tube 2 while a short tube 6 equipped with a flange, divided into a plurality of parts so as to have a length (l) same as the reduced length of the spout, is interposed in said connecting part. Next, the divided short tube is welded to integrate it. When the divided parts 6a-6c the short tube 6 are assembled and connected, a short tube having the same shape as the center spout may be obtained. On the other hand, the short tube 6 is provided with a partitioning plate 7 for the short tube, which is connected to the partitioning plate of the center spout, whereby there is no hindrance in the dividing of the supply of material.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for repairing a three-phase L-type electric furnace.

(Original [Prior Art] Figure 4 1al and fbl show an example of spout arrangement in a three-phase L-type electric furnace, fat is a plan view, fb is
Figure l is a diagram showing the A-A cross section of the field diagram. 10 is the electric furnace main body, 11 is the furnace lid, 12 is the electrode, 13 is the t-pole holder, 14 is the raw material supply into the electric furnace. A large number of spouts are chutes and are arranged to penetrate the furnace lid 11.A raw material input pipe 2 is connected to each of these spouts. Since the raw material input pipes must be gathered in a very narrow area surrounded by the three electrodes 12, these raw material input pipes are collectively connected to the central spout 1.

Raw materials are supplied to the electric furnace by keeping the spout and raw material input pipe filled with the raw materials at all times. Therefore, the raw material level is always maintained constant. However, during long-term operation, there will be damage to the spout due to high heat and wear, and the damage will start from the lower end,
The dimensions of the spout become progressively shorter. When the length of the spout becomes shorter (hereinafter referred to as reduction), the raw material level changes from Lo to Ll, for example, as shown in Figure 4 fbl.
and increases with spout damage. If this state is left as it is, there is a risk that the raw material will come into contact with the electrode holder 13.

For this reason, a spout that has been reduced in size to the limit must be restored to its original length; however, spouts are arranged in large numbers on the chivalry, especially the central spout l.
Since it is arranged in a very narrow area surrounded by the electrode 12, it is extremely difficult to extract it outside the furnace. Therefore, the damaged part cannot be repaired,
The damaged spout is dropped into the furnace and a new spout is installed for renewal. Spout replacement is carried out by removing the furnace lid and inserting a new spout from inside the furnace.

[Problems to be Solved by the Invention] In the above-mentioned prior art, there is a problem in that if the spout is damaged and reduced in size, it cannot be repaired and the entire spout must be renewed. Moreover, when updating,
Since a new spout cannot be inserted or removed from the top of the furnace lid, it is essential to remove the furnace lid and insert a new spout from inside the furnace. Furthermore, in this case,
The temperature inside the furnace must drop to a level that allows workers to enter, so the electric furnace must be shut down for a long period of time (usually about a month) to cool the inside of the furnace, and production has to be halted during this time. be done.

The present invention solves the above problems of the prior art and provides a spout repair method for an electric furnace that can repair a damaged spout without requiring a long-term shutdown of the electric furnace and without replacing the spout. purpose.

[Means and effects for solving the problem] In order to achieve the above object, in the present invention, the connection between the reduced spout and the raw material input pipe is separated, and the spout is connected to the same length as the reduced length. After dividing the short pipe into a plurality of parts and inserting them into the connecting part, the two divided short pipes are joined and integrated to restore the reduced spout to the length before the reduction.

The present invention is a method that allows easy repair of a spout while it remains attached to an electric furnace. Moreover, since the short pipe to be inserted during repair is divided into a plurality of parts, repair is even easier.

Through this repair, the height of the lower end of the reduced spout in the electric furnace becomes the same as the lower end height of the spout before the reduction, and the raw material level becomes normal.

Since this repair work is performed outside the furnace (on the furnace lid), it is only necessary to stop the electric furnace for a short period of time.

[Example] Hereinafter, as a representative example of the embodiment of the present invention, a method for repairing a central spout, which is extremely difficult to extract from the furnace, will be described.

Figure 3 fa) and fbl show the damaged central spout, where (a) is a side view and fbl is a plan view.

A plurality of raw material input pipes 2 are connected to the central spout 1, and the inside thereof is divided into a plurality of parts by a partition plate 3, and the raw materials supplied from each raw material input pipe 2 are divided and charged into the furnace. It looks like this. The connecting portion 4 between the central spout 1 and the raw material input pipe 2 is flange-jointed.

5 is the part that has disappeared due to damage, and this central spout 1 is shorter by a length 1 than its original size.

FIG. 1 shows one embodiment of the present invention, and is a side view of a state in which the central spout has been repaired. Repair the reduced central spout as follows: First, temporarily stop the electric furnace and disconnect the flange at the connection between the central spout 1 and the raw material input pipe 2 provided on the furnace lid.Next, lower the central spout 1 and connect the central spout 1 and the raw material input pipe 2. The flanged short pipe 6 divided into a plurality of parts as shown in FIG. Weld the tubes together. 8 shows a welding line, FIG. 2 is a plan view showing an interposed short pipe, and the short pipe 6 is a short pipe divided portion 6 a + 6 b
If you assemble r 6 c and join them together, it will have the same shape as the central spout. Also, short pipe 6
A short pipe partition plate 7 is provided in connection with the partition plate of the central spout, so that there is no problem in the division of raw material supply.

By inserting the short pipe 3, the length of the central spout is restored to the length before the reduction.

The above repair can be completed in a few hours. Therefore, stopping the electric furnace only takes a few hours.

[Effects of the Invention] The present invention repairs a damaged spout while it is still attached to the electric furnace without renewing it. The method of the present invention, which is a method of restoring the spout to its original length by inserting a pipe into the connection between the spout and the raw material input pipe, includes:
Since the repair method involves inserting a short pipe, the repair can be completed in a very short time. Moreover, since the short pipe to be inserted is divided into a plurality of parts, the construction is easier.

Therefore, in the conventional technology, it was necessary to stop the electric furnace for repairs for more than a month, but
According to the present invention, it only takes a few hours, which greatly contributes to improving productivity.

[Brief explanation of drawings]

Fig. 1 is a side view showing an embodiment of the present invention with the central spout repaired; Fig. 2 is a diagram showing an interposed short pipe;
FIG. 3 is a diagram showing a damaged central spout, and FIG. 4 is a diagram showing an example of spout arrangement in a three-phase L-type electric furnace. 1... Central spout, 2... Raw material input pipe, 3...
Partition plate, 4... Connection part, 5... Portion lost due to damage, 6... Short pipe with flange, 6a, 6b, 6c
...Short pipe division part, 7...Short pipe partition plate, 10...
・Electric furnace body, 11... Furnace lid 512... Electrode, 13
...electrode holder, 14...spout.

Claims (1)

[Claims] In a method for repairing a spout of a three-phase electric furnace whose size has been reduced due to damage, the connecting portion between the reduced size spout and the raw material input pipe is cut off, and the spout has the same length as the reduced size. The spout is divided into a plurality of parts and inserted into the connecting part, and then the divided short pipes are joined and integrated to restore the reduced spout to the length before the reduction. How to repair an electric furnace spout.